Interference lithography system and method based on electro-optical deflection phase shifting and synchronous image rotation

Abstract

The present invention discloses an interference lithography system and method based on electro-optical deflection phase shifting and synchronous image rotation. The present invention realizes phase modulation of two polarized lights by controlling the laser phase and spatial distribution modulation module, so that the position of interference fringes can be flexibly adjusted. The spacing of two parallel laser beams can be modulated by changing the beam angles of the two polarized lights, so that the arrangement period of interference fringes can be flexibly adjusted. The present invention also realizes controllable rotation of two laser beams by controlling the image rotation module, so that the periodic direction of interference fringes can be flexibly adjusted. In summary, the present invention can realize flexible regulation of interference patterns. Since the present invention regulates fewer modules, only the laser phase and spatial distribution modulation module and the image rotation module are controlled, the error caused in the regulation process is less, so the accuracy of regulation is higher.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser direct writing, and in particular relates to an interference lithography system and method based on electro-optical deflection phase shifting and synchronous image rotation. Background Art

[0002] The production of micro-nano structures with specific structures on the surface of materials has always been a research focus in the field of microelectronics and nanoscience. However, the size limitations and high costs of traditional photolithography methods make it impossible to mass-produce large-area micro-nano patterns with flexible periodic scales. The production of these specific periodic structures is a core technology in the fields of microelectronic device manufacturing, biomedicine, and electronic detection. Therefore, low-cost mass production of large-area micro-nano structures has extremely high market value.

[0003] Optical interference lithography is an important technology for manufacturing micro-nano array devices by exposing a photosensitive substrate to a periodic pattern generated by the interference of two or more laser beams. The laser interference lithography method has an incomparable advantage in the low-cost, large-scale, large-area manufacturing of surface micro-nano structures, especially when making periodic structures from a few hundred nanometers to a few microns. The laser interference lithography method can complete the work very simply and at a low cost. These periodic structures include gratings, dot arrays, and linear array structures. Then, using the etching methods commonly used in the field of microelectronics, these micro-nano structures can be transferred to the substrate, so that laser interference lithography can be applied in more fields.

[0004] The invention patent application with publication number CN102838082A discloses a method for making micro-nano structures on the surface of a material based on laser interference lithography. It forms micro-nano structures on a photoresist by generating laser interference, and then transfers the micro-nano structures on the photoresist to the surface of a substrate material by etching to form micro-nano scale gratings, dot arrays, linear arrays and other structures. The method of the present invention can be used to make high-quality nanostructures on the surface of various materials in a large area, which is simple and low-cost and has great application value. However, the writing freedom is low, and various microstructure morphologies and arrangements cannot be flexibly realized.

[0005] The invention patent application with publication number CN110837214 discloses a scanning interference lithography system, including a heterodyne optical path, a first interference optical path, a second interference optical path, a moving stage and a control subsystem; the moving stage carries a substrate, the displacement of the moving stage is measured by a displacement measuring interferometer, and the first beam of light and the second beam of light are focused on the substrate for interference exposure; the control subsystem generates instructions according to various measurement information, adjusts the angle of the corresponding device or the phase of the light beam, and completes the locking of the phase drift of the interference exposure stripes of the first beam of light and the second beam of light. The scanning interference lithography system of the present invention has the advantages of high stripe pattern locking accuracy and high laser utilization rate. The phase of the exposure beam is measured by a heterodyne phase meter, and the motion error of the moving stage is measured by a displacement measuring interferometer. The exposure interference stripes are compensated and controlled by the control subsystem, and can be used to manufacture large-area high-precision dense grid line gradient periodic gratings. However, the patent application requires more optical devices to be regulated, and the control is complex, making it difficult to achieve accurate regulation. Summary of the invention

[0006] The present invention provides an interference lithography system based on electro-optical deflection phase shifting and synchronous image rotation, which can flexibly control the surface morphology and arrangement of various microstructures by controlling fewer devices, with fewer errors and higher accuracy during the control process.

[0007] The present invention provides an interference lithography system based on electro-optical deflection phase shifting and synchronous image rotation, comprising:

[0008] Laser output module, used to generate and calibrate laser;

[0009] The laser beam splitting and polarization modulation module is used to convert the calibrated laser into polarized light, split the parallel polarized light into two laser beams, and adjust the polarization direction of one of the laser beams so that the polarization directions of the two laser beams are consistent;

[0010] The laser phase and spatial distribution modulation module is used to adjust the direction of polarized light to form two polarized lights, and adjust the phase difference between the two polarized lights. It is also used to adjust the propagation direction of the two polarized lights so that the two polarized lights form parallel polarized lights through the scanning lens. At the same time, it can adjust the spacing between the two parallel laser beams by changing the beam angles of the two polarized lights. It is also used to obtain the two parallel laser beams by changing the propagation direction of the two laser beams.

[0011] An image rotation module is used to rotate two or any one of the parallel emitted laser beams so that the plane where the two or any one of the laser beams are located changes;

[0012] A laser beam combining direct writing module is used to focus two rotated parallel outgoing laser beams on the photoresist to form an interference fringe pattern;

[0013] An illumination monitoring module is used to illuminate the interference fringe pattern to obtain scattered light, and to focus the scattered light onto a camera, and to obtain an image of the interference fringe pattern through the camera;

[0014] The acquisition control module is used to receive the image of the interference fringe pattern and synchronously control the laser phase and spatial distribution modulation module and the image rotation module to adjust the interference fringe pattern.

[0015] Preferably, the laser phase and spatial distribution modulation module comprises an electro-optic modulator, a fast deflection mirror, a scanning lens, a second plane mirror, a third plane mirror and a right-angle plane mirror;

[0016] The electro-optic modulator is used to modulate the phase difference of polarized light;

[0017] The fast deflection mirror is used to adjust the propagation direction of the two polarized lights so that the two polarized lights form parallel polarized lights through the scanning lens, and can also adjust the distance between the two parallel laser beams by changing the beam angles of the two polarized lights;

[0018] The two laser beams are respectively reflected to the right-angle plane mirror by the second plane mirror and the third plane mirror, and two parallel laser beams are obtained by direct plane mirror reflection.

[0019] Preferably, the fast deflection mirror is located on the front focal plane of the scanning lens, and the fast deflection mirror comprises a fast deflection stage and a plane mirror;

[0020] The fast tilt table is connected to the acquisition control module and is used to rotate based on the instructions of the acquisition control module;

[0021] The plane mirror is used to adjust the propagation direction of the two polarized lights so that the two polarized lights form parallel polarized lights through the scanning lens, and can also adjust the spacing between the two parallel laser beams by changing the beam angles of the two polarized lights.

[0022] Preferably, the laser phase and spatial distribution modulation module further comprises a first plane mirror, and the first plane mirror is used to reflect the parallel polarized light to the laser beam splitting and polarization modulation module.

[0023] Preferably, the laser beam combining direct writing module comprises a first lens, a variable aperture, a second lens, an objective lens and a translation stage;

[0024] The first lens and the scanning lens form a 4f system, and the first lens is used to irradiate two parallel outgoing laser beams to the variable aperture;

[0025] The variable iris forms a conjugate image with the fast deflection mirror. The two laser beams passing through the variable iris are focused on the rear focal plane of the objective lens through the second lens, and then interfere on the photoresist of the displacement stage to form an interference fringe pattern. The field size of the interference fringe pattern can be changed by changing the size of the variable iris.

[0026] Preferably, the acquisition control module includes a computer and a data acquisition card;

[0027] The computer is respectively connected to the camera and the data acquisition card through communication, and the computer is used to receive the image of the interference fringe pattern and send instructions to the data acquisition card;

[0028] The data acquisition card is used to synchronously control the electro-optic modulator, the fast deflection mirror and the image rotation module based on the received instructions so as to adjust the interference fringe pattern.

[0029] Preferably, the lighting monitoring module comprises a dichroic mirror, an illumination LED, a tube lens and a camera;

[0030] The illumination LED is used to illuminate the interference fringe pattern to obtain scattered light;

[0031] The scattered light is focused onto a camera through the dichroic mirror and the tube lens, and an image of the interference fringe pattern is obtained by photographing the camera.

[0032] Preferably, the laser beam splitting and polarization modulation module comprises a first half-wave plate, a polarization beam splitter and a second half-wave plate;

[0033] The first half-wave plate is used to convert the calibrated laser light into polarized light;

[0034] The polarization beam splitter is used to split parallel polarized light into two laser beams;

[0035] The second half-wave plate is used to adjust the polarization direction of one of the laser beams so that the polarization directions of the two laser beams are consistent.

[0036] Preferably, the image rotation module comprises a fourth plane mirror, a fifth plane mirror and a sixth plane mirror, the angle between the fourth plane mirror and the fifth plane mirror is an obtuse angle, and the sixth plane mirror is horizontally placed above the fourth plane mirror and the fifth plane mirror;

[0037] The two parallel laser beams are reflected three times by the fourth plane mirror, the sixth plane mirror and the fifth plane mirror in sequence, so that the planes where the two or any one of the laser beams are located are changed, thereby obtaining two rotated parallel laser beams.

[0038] On the other hand, the present invention further provides a method for interference lithography based on electro-optical deflection phase shifting and synchronous image rotation, which uses the interference lithography system based on electro-optical deflection phase shifting and synchronous image rotation to perform interference lithography, comprising:

[0039] Produce and calibrate laser light through the laser output module;

[0040] Changing the direction of the laser light by the first half-wave plate to form polarized light;

[0041] Modulating the polarized light by the electro-optical modulator to form two polarized lights, and modulating the phase difference between the two polarized lights, thereby changing the position of the interference fringes on the photoresist;

[0042] The propagation directions of the two polarized lights are regulated by the fast deflection mirror, so that the two polarized lights become parallel polarized lights after passing through the scanning lens, and the distance between the two parallel laser beams is changed by regulating the beam angles of the two polarized lights;

[0043] The parallel polarized light is split into two mutually perpendicular laser beams by the fast deflection mirror, and any one of the laser beams is polarized by the second half-wave plate so that the polarization directions of the two laser beams are the same;

[0044] Changing the propagation directions of the two laser beams so that the two laser beams are emitted in parallel, rotating the two or any one of the laser beams emitted in parallel by the image rotation module, thereby adjusting the periodic direction of the interference fringes on the photoresist;

[0045] The interference fringe pattern is illuminated by the illumination monitoring module to obtain scattered light, and the scattered light is focused onto a camera, and an image of the interference fringe pattern is obtained by photographing the camera;

[0046] The image of the interference fringe pattern is received by the acquisition control module, and the laser phase and space distribution modulation module and the image rotation module are synchronously controlled to adjust the interference fringe pattern.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] The present invention realizes phase modulation of two polarized lights by controlling the laser phase and spatial distribution modulation module, so that the position of interference fringes can be flexibly adjusted. The spacing of two parallel laser beams can be modulated by changing the beam angles of the two polarized lights, so that the arrangement period of interference fringes can be flexibly adjusted. The present invention also realizes controllable rotation of two laser beams by controlling the image rotation module, so that the periodic direction of interference fringes can be flexibly adjusted. In summary, the present invention can realize flexible regulation of interference patterns. Since the present invention regulates fewer modules, only the laser phase and spatial distribution modulation module and the image rotation module are controlled, the error caused in the regulation process is less, so the accuracy of regulation is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1A schematic diagram of the principle of an interference super-resolution lithography system based on electro-optical high-speed phase shifting provided in a specific embodiment of the present invention.

[0050] Figure 2 A schematic diagram of an image rotation module provided in a specific embodiment of the present invention.

[0051] Figure 3 A schematic diagram of an interference fringe pattern obtained by step-scanning lithography of an interference super-resolution lithography system based on electro-optical high-speed phase shifting provided in a specific embodiment of the present invention.

[0052] Figure 4 A schematic diagram of an interference fringe pattern obtained by continuous scanning lithography of an interference super-resolution lithography system based on electro-optical high-speed phase shifting provided in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0053] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0054] In this embodiment, an interference lithography method based on electro-optical deflection phase shifting and synchronous image rotation is provided. Figure 1 FIG. 1 is a schematic diagram of the principle of an interference lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to the preferred embodiment of the present invention. Figure 1 As shown, according to the optical path arrangement, it includes: a high-power laser 1, a beam collimator 2, a first half-wave plate 3, an electro-optic modulator 4, a fast deflection mirror 5, a scanning lens 6, a first plane mirror 7, a polarization beam splitter 8, a second plane mirror 9, a right-angle plane mirror 10, a second half-wave plate 11, a third plane mirror 12, an image rotation module 13, a first lens 14, a variable aperture 15, a second lens 16, a dichroic mirror 17, an objective lens 18, a translation stage 19, an illumination LED 20, a tube lens 21, a camera 22, a computer 23, and a data acquisition card 24.

[0055] The laser output module provided in a specific embodiment of the present invention comprises a high-power laser 1 and a beam collimator 2. The high-power laser 1 is used to generate high-power coherent laser light, and the beam collimator 2 is used to expand the beam and complete the beam collimation calibration.

[0056] The laser beam splitting and polarization modulation module provided in a specific embodiment of the present invention includes a first half-wave plate 3, a polarization beam splitter 8 and a second half-wave plate 11. The first half-wave plate 3 converts the output laser into polarized light, so that the laser beam irradiated to the polarization beam splitter 8 can be divided into two polarized lights of equal intensity; the second half-wave plate 11 causes the polarization direction of one of the laser beams to be deflected by 90°, so that the polarization directions of the two laser beams are the same, thereby achieving a stripe pattern with sufficiently high contrast when the final beam is combined for interference, meeting the excitation threshold of lithography, and realizing lithography writing.

[0057] The laser phase and spatial distribution modulation module provided in a specific embodiment of the present invention includes an electro-optic modulator 4, a fast deflection mirror 5, a scanning lens 6, a first plane mirror 7, a second plane mirror 9, a right-angle plane mirror 10, and a third plane mirror 12. The electro-optic modulator 4 is used to divide the polarized light modulated by the first half-wave plate 3 into o light and e light of equal light intensity, which respectively correspond to the two interference lights split by the subsequent optical path through the polarization beam splitter 8. The electro-optic modulator 4 modulates the phase difference between the o light and the e light through the electro-optic effect, thereby changing the position of the final interference fringe, that is, it is used to modulate the phase difference of the two laser beams, so that the position of the fringe after the two laser beams are combined and interfered is controllably displaced; the fast deflection mirror 5 is composed of a fast deflection table and a plane mirror, and is placed on the front focal plane of the scanning lens 6 to ensure that the light of each angle is emitted in a direction parallel to the main optical axis after passing through the scanning lens, so that the light beam is divided into two mutually perpendicular light beams after passing through the first plane mirror 7 and the polarization beam splitter 8, and is respectively irradiated onto the right-angle plane mirror 10 after passing through the second plane mirror 9 and the third plane mirror 12, and the reflected light remains parallel to each other. At the same time, the beam angle changed by the fast deflection mirror 5 affects the spacing between the two beams after reflection from the right-angle plane mirror 10, and further controls the fringe period after the two light beams are combined and interfered, meeting the flexible lithography requirements.

[0058] The image rotation module 13 provided in the specific embodiment of the present invention is used to change the direction of the plane where the two beams of light are located, so as to control the periodic direction of the interference fringes after the combined beams. Figure 2 The schematic diagram of the image rotation module 13 is composed of three plane mirrors, two of which are symmetrically placed with an obtuse angle, and the other reflector is placed horizontally on top, so that the two parallel laser beams are reflected three times respectively and then exchange positions and emit in parallel. In a specific embodiment, the three plane mirrors are fixed on a housing as a whole and are equipped with a high-precision motor to control the rotation along the axis, so that the emitted light is not limited to Figure 2 The angle shown is flipped 180°, and it can be rotated at any angle to achieve free rotation of the final interference fringe direction.

[0059] The laser beam combining direct writing module provided in a specific embodiment of the present invention includes a first lens 14, a variable aperture 15, a second lens 16, an objective lens 18, and a displacement stage 19. The first lens 14 and the scanning lens 6 constitute a 4f system, which conjugates the fast deflection mirror 5 and the variable aperture 15 to form an image; the variable aperture 15 can affect the size of the interference fringe field of view of the final imaging of the objective lens by changing the size of the aperture; the light beam passing through the variable aperture is focused on the rear focal plane of the objective lens 18 through the second lens 16, and then the two laser beams interfere in the photoresist on the displacement stage 19 behind the objective lens to form stripes, thereby completing the excitation lithography.

[0060] The lighting monitoring module provided by the specific embodiment of the present invention includes a dichroic mirror 17, an illumination LED 20, a tube lens 21, and a camera 22. The illumination LED 20 allows the light scattered by the inscribed structure to pass through the dichroic mirror 17, and then is focused on the camera 22 through the tube lens 21, and the image of the interference fringe pattern is obtained by the camera.

[0061] The acquisition control module provided in the specific embodiment of the present invention includes a computer 23 and a data acquisition card 24. The image captured by the camera 22 is transmitted to the computer 23 through the network card communication. At the same time, the computer can send instructions to the data acquisition card 24 according to the captured image, thereby controlling the switch, exposure time and other parameters of the camera. The displacement stage 19 feeds back the current position coordinates and speed information to the data acquisition card 24 in real time. At the same time, the data acquisition card 24 sends instructions to control the displacement stage to complete the movement through the command of the computer. The data acquisition card 24 realizes the synchronous control of the electro-optic modulator 4, the fast deflection mirror 5, the image rotation module 13, the displacement stage 19 and the camera 22.

[0062] like Figure 3 As shown, two laser beams interfere on the displacement stage to form interference fringes with equal spacing. After the interference fringes are exposed at a certain position for a period of time, the displacement stage 19 steps a distance of a field of view to the next field of view. The computer 23 issues instructions to the data acquisition card 24 to control the laser phase and spatial distribution modulation module and the image rotation module 13 to complete the precise control of the direction and position of any interference fringes, and then expose again, and the cycle is repeated until the exposure of all structures is completed. It is worth noting that only four interference patterns are listed in the figure. In actual writing, the direction and period of the interference fringes can be arbitrarily controlled, and can be arranged and stepped in any direction on a two-dimensional plane, not limited to the schematic diagram.

[0063] like Figure 4 As shown, two laser beams interfere on the displacement stage 19 to form interference fringes with equal spacing. At the same time, the displacement stage 19 moves at a constant speed along the direction of the interference fringes, thereby exposing a row of line arrays of arbitrary length in the field of view. During the movement of the displacement stage 19, the illumination monitoring module can detect the platform position and the morphology of the writing fringes in real time. If there is a deviation in a certain direction, the laser phase and spatial distribution modulation module and the image rotation module 13 can be manipulated to finely control the interference fringes in real time, so that the exposed fringes are uniform and straight.

Claims

1. An interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation, characterized in that: include: Laser output module, used to generate and calibrate laser; The laser beam splitting and polarization modulation module is used to convert the calibrated laser into polarized light, split the parallel polarized light into two laser beams, and adjust the polarization direction of one of the laser beams so that the polarization directions of the two laser beams are consistent; The laser phase and spatial distribution modulation module is used to adjust the direction of polarized light to form two polarized lights, and adjust the phase difference between the two polarized lights. It is also used to adjust the propagation direction of the two polarized lights so that the two polarized lights form parallel polarized lights through the scanning lens. At the same time, it can adjust the spacing between the two parallel laser beams by changing the beam angles of the two polarized lights. It is also used to obtain the two parallel laser beams by changing the propagation direction of the two laser beams. An image rotation module is used to rotate two or any one of the parallel emitted laser beams so that the plane where the two or any one of the laser beams are located changes; A laser beam combining direct writing module is used to focus two rotated parallel outgoing laser beams on the photoresist to form an interference fringe pattern; An illumination monitoring module is used to illuminate the interference fringe pattern to obtain scattered light, and to focus the scattered light onto a camera, and to obtain an image of the interference fringe pattern through the camera; An acquisition control module is used to receive an image of the interference fringe pattern and synchronously control the laser phase and spatial distribution modulation module and the image rotation module to adjust the interference fringe pattern; The laser phase and spatial distribution modulation module comprises an electro-optic modulator, a fast deflection mirror, a scanning lens, a second plane mirror, a third plane mirror and a right-angle plane mirror; The electro-optic modulator is used to modulate the phase difference of polarized light; The fast deflection mirror is used to adjust the propagation direction of the two polarized lights so that the two polarized lights form parallel polarized lights through the scanning lens, and can also adjust the distance between the two parallel laser beams by changing the beam angles of the two polarized lights; The two laser beams are respectively reflected to the right-angle plane mirror by the second plane mirror and the third plane mirror, and two parallel laser beams are obtained by direct plane mirror reflection.

2. The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to claim 1, characterized in that: The fast deflection mirror is located on the front focal plane of the scanning lens, and the fast deflection mirror includes a fast deflection stage and a plane mirror; The fast tilt table is connected to the acquisition control module and is used to rotate based on the instructions of the acquisition control module; The plane mirror is used to adjust the propagation direction of the two polarized lights so that the two polarized lights form parallel polarized lights through the scanning lens, and can also adjust the spacing between the two parallel laser beams by changing the beam angles of the two polarized lights.

3. The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to claim 1, characterized in that: The laser phase and spatial distribution modulation module further comprises a first plane mirror, which is used to reflect parallel polarized light to the laser beam splitting and polarization modulation module.

4. The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to claim 1, characterized in that: The laser beam combining direct writing module comprises a first lens, a variable aperture, a second lens, an objective lens and a translation stage; The first lens and the scanning lens form a 4f system, and the first lens is used to irradiate two parallel outgoing laser beams to the variable aperture; The variable iris forms a conjugate image with the fast deflection mirror. The two laser beams passing through the variable iris are focused on the rear focal plane of the objective lens through the second lens, and then interfere on the photoresist of the displacement stage to form an interference fringe pattern. The field size of the interference fringe pattern can be changed by changing the size of the variable iris.

5. The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to claim 1, characterized in that: The acquisition control module includes a computer and a data acquisition card; The computer is respectively connected to the camera and the data acquisition card through communication, and the computer is used to receive the image of the interference fringe pattern and send instructions to the data acquisition card; The data acquisition card is used to synchronously control the electro-optic modulator, the fast deflection mirror and the image rotation module based on the received instructions so as to adjust the interference fringe pattern.

6. The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to claim 1, characterized in that: The lighting monitoring module includes a dichroic mirror, an illumination LED, a tube mirror and a camera; The illumination LED is used to illuminate the interference fringe pattern to obtain scattered light; The scattered light is focused onto a camera through the dichroic mirror and the tube lens, and an image of the interference fringe pattern is obtained by photographing the camera.

7. The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to claim 1, characterized in that: The laser beam splitting and polarization modulation module comprises a first half-wave plate, a polarization beam splitter and a second half-wave plate; The first half-wave plate is used to convert the calibrated laser light into polarized light; The polarization beam splitter is used to split parallel polarized light into two laser beams; The second half-wave plate is used to adjust the polarization direction of one of the laser beams so that the polarization directions of the two laser beams are consistent.

8. The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation according to claim 1, characterized in that: The image rotation module comprises a fourth plane mirror, a fifth plane mirror and a sixth plane mirror, the included angle between the fourth plane mirror and the fifth plane mirror is an obtuse angle, and the sixth plane mirror is horizontally placed above the fourth plane mirror and the fifth plane mirror; The two parallel laser beams are reflected three times by the fourth plane mirror, the sixth plane mirror and the fifth plane mirror in sequence, so that the planes where the two or any one of the laser beams are located are changed, thereby obtaining two rotated parallel laser beams.

9. A method for interference lithography based on electro-optical deflection phase shifting and synchronous image rotation, characterized in that: The interferometric lithography system based on electro-optical deflection phase shifting and synchronous image rotation as claimed in any one of claims 1 to 8 is used to perform interferometric lithography, comprising: Produce and calibrate laser light through the laser output module; The direction of the laser light is changed by the first half-wave plate to form polarized light; The polarized light is modulated by an electro-optical modulator to form two polarized lights, and the phase difference between the two polarized lights is modulated, thereby changing the position of the interference fringes on the photoresist; The propagation direction of the two polarized lights is regulated by a fast deflection mirror, so that the two polarized lights become parallel polarized lights after passing through the scanning lens. The distance between the two parallel laser beams is also changed by regulating the beam angles of the two polarized lights. The parallel polarized light is split into two mutually perpendicular laser beams by a fast deflection mirror, and any one of the laser beams is polarized by a second half-wave plate so that the polarization directions of the two laser beams are the same; Changing the propagation directions of the two laser beams so that the two laser beams are emitted in parallel, rotating the two or any one of the laser beams emitted in parallel by the image rotation module, thereby adjusting the periodic direction of the interference fringes on the photoresist; The interference fringe pattern is illuminated by the illumination monitoring module to obtain scattered light, and the scattered light is focused onto a camera, and an image of the interference fringe pattern is obtained by photographing the camera; The image of the interference fringe pattern is received by the acquisition control module, and the laser phase and space distribution modulation module and the image rotation module are synchronously controlled to adjust the interference fringe pattern.

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